Thomas Robert Cech is an American chemist who shared the 1989 Nobel Prize in Chemistry with Sidney Altman, for their discovery of the catalytic properties of RNA. Cech discovered that RNA could itself cut strands of RNA, which showed that life could have started as RNA. He also studied telomeres, and his lab discovered an enzyme, TERT, which is part of the process of restoring telomeres after they are shortened during cell division. As president of Howard Hughes Medical Institute, he promoted science education, and he teaches an undergraduate chemistry course at the University of Colorado. He was born on December 8, 1947 in Chicago, Illinois, United States. In 1975, Cech completed his PhD in Chemistry at the University of California, Berkeley and in the same year, he entered the Massachusetts Institute of Technology where he engaged in postdoctoral research. In 1978, he obtained his first faculty position at the University of Colorado where he lectured undergraduate students in chemistry and biochemistry, and where he remains on the faculty, currently as Distinguished Professor in the Department of Chemistry and Biochemistry. In 2000, Cech succeeded Purnell Choppin as president of the Howard Hughes Medical Institute in Maryland. He also continues to head his biochemistry laboratory, the Colorado Initiative in Molecular Biotechnology, at the University of Colorado, Boulder. Cech continues to teach undergraduate chemistry at CU-Boulder. On April 1, 2008, Cech announced that he would step down as the president of HHMI, to return to teaching and research, in spring 2009.

Cech's work has been recognised by many awards and prizes including: lifetime Professorship by the American Cancer Society (1987),the Louisa Gross Horwitz Prize from Columbia University(1988), the Heineken Prize of the Royal Netherlands Academy of Sciences (1988), the Albert Lasker Basic Medical Research Award (1988), the Nobel Prize in Chemistry (1989, shared with Sidney Altman) and the National Medal of Science (1995). In 1987, Cech was elected to the United States National Academy of Sciences and in 1988 he was elected to the American Academy of Arts and Sciences. In 2007, he received the Othmer Gold Medal for outstanding contributions to progress in chemistry and science.